const myPlugin={
   install(Vue,options){
    Vue.component("message",{
      mixins:[myMaxin],
      props: {
          show: {
              type: Boolean,
              default: false
          },
      },
      template:`
      <transition name="fade">
          <div class="message-box" v-if="show" style="position:relative;width:200px;height:100px;background:pink;">
              <slot name="title2" title="来自子组件的title" >默认标题</slot>
              <slot></slot>
              <span style="position:absolute;top:10px;right:10px;" @click="$emit('update:show',false)">哈哈哈X</span>
              <div @click="callFun()">21423</div>
          </div>
      </transition>
      `
  })
   }
}